Description

Persistent connections are cached and re-used between requests, resulting
in reduced overhead on each page load; a typical PHP application will have
a single persistent connection open against an Oracle server per Apache
child process (or PHP FastCGI/CGI process). See the Persistent Database
Connections section for more information.

Parameters

username

The Oracle user name.

password

The password for username
.

db

This optional parameter can either contain the name of the local
Oracle instance or the name of the entry in
tnsnames.ora.

If the not specified, PHP uses environment variables
ORACLE_SID and TWO_TASK to
determine the name of local Oracle instance and location of
tnsnames.ora accordingly.

charset

Using Oracle server version 9.2 and greater, you can
indicate charset
by parameter, which will be used in the new
connection. If you're using Oracle server < 9.2, this parameter will be ignored
and the NLS_LANG environment variable will be used instead.

session_mode

This parameter is available since version 1.1 and accepts the
following values: OCI_DEFAULT,
OCI_SYSOPER and OCI_SYSDBA.
If either OCI_SYSOPER or
OCI_SYSDBA were specified, this function will try
to establish privileged connection using external credentials.
Privileged connections are disabled by default. To enable them you
need to set oci8.privileged_connect
to On.

Note:
In PHP versions before 5.0.0 you must use ociplogon() instead.
This name still can be used, it was left as alias of
oci_pconnect() for downwards compatability.
This, however, is deprecated and not recommended.